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Biomedical subjects

K Tajima

Publications and source records attributed to K Tajima.

At least 325 records · Page 18Linked to original sources

Establishment from a human chondrosarcoma of a new immortal cell line with high tumorigenicity in vivo, which is able to form proteoglycan-rich cartilage-like nodules and to respond to insulin in vitro.

The human chondrosarcoma cell line (HCS-2/8) established by our group expresses cartilage phenotypes such as production of cartilage-type proteoglycans and collagen type II, but its tumorigenicity is low. To develop an in vitro experimental system for studies of human chondrosarcomas, a new immortal cell line of human chondrosarcoma, named HCS-2/A, was established from the same tumor. HCS-2/A cells proliferated with a doubling time of 3 1/2 days in a medium containing 20% fetal bovine serum (FBS). This growth rate was comparable to that of HCS-2/8 cells. However, HCS-2/A cells proliferated more rapidly than HCS-2/8 cells in the presence of 2-10% FBS. Like HCS-2/8 cells, HCS-2/A cells had a polygonal shape in sparse cultures and became spherical as they reached confluence, after which they formed nodules composed of multilayered cells and a large quantity of extracellular matrix showing strong metachromasia. The nodules formed by HCS-2/A cells were thicker and also larger in diameter than those formed by HCS-2/8 cells. Electron microscopically, the cells in the nodules resembled chondrocytes in vivo, but each cell had an irregular-shaped nucleus which is a characteristics of tumor cells. The cells actively synthesized "cartilage-specific" large proteoglycans and their level of proteoglycan synthesis was comparable to that of HCS-2/8 cells. Insulin, which stimulates proteoglycan and DNA syntheses in cultured chondrocytes, markedly increased proteoglycan synthesis in HCS-2/A cells. On the other hand, the hormone only slightly increased proteoglycan synthesis in HCS-2/8 cells. Insulin also stimulated DNA synthesis in cultured HCS-2/A cells, but not in HCS-2/8 cells. Immunostaining revealed that HCS-2/A cells produced type-II collagen but not type-I collagen. However, the level of collagen synthesis of HCS-2/A cells was lower than that of HCS-2/8 cells. Inoculation of HCS-2/A cells into athymic mice resulted in the formation of chondrosarcomas that grew faster than those arising from HCS-2/8 cells.

Aged↗

Coordination structure and chemical reactivity of hemoprotein-butyl peroxide complex.

ESR and optical spectra ascribed to be the hemoprotein-butylperoxide complex were detected for the frozen aqueous solution containing whale met-Mb and t- or n-butylhydroperoxide at pH 10. The observed ESR and optical parameters of the complex were characteristic to those of six coordinate ferric low-spin complexes, having the butylperoxide anion at the axial position of heme. pH dependent ESR measurements demonstrated the formation of the complex in the biological pH regions (7.0). Time dependent ESR and optical measurements indicated that the complex may be one of the intermediate species in the processes of heme degradation reaction induced by butylperoxide.

Animals↗

Localization of blood coagulation factors and fibrinolysis factors within lymphoid germinal centers in human lymph nodes.

The presence of nineteen blood coagulation factors and fibrinolysis factors was immunohistochemically evaluated in human lymph node germinal centers (GCs). Twelve of these factors were detected within lymphoid GCs. The predominant pattern was dendritic with occasional crescent-shaped, ring-shaped or 'moth-eaten' appearance. Immunostains of factor VIII-related antigen, factor I, protein C, tetranectin, antithrombin III, type 2-plasminogen activator inhibitor, and alpha 2-plasmin inhibitor were almost entirely absent from GCs, although they reacted in vascular wall and lumen, respectively. The immunostaining to high molecular weight kininogen, kallikrein, factors XII, X, V, II, XIIIa, XIIIs, plasminogen, tissue-plasminogen activator, and type 1-plasminogen activator inhibitor more frequently revealed a positive dendritic pattern. Immuno-electron microscopy demonstrated factor X and factor XIIIa attached to the cell surfaces of lymphocytes, macrophages, and follicular dendritic cells (FDCs); and in the intercellular space within GCs, especially attached to the labyrinthine-like structure of FDCs. No reaction products were observed in the perinuclear cisternae and rough endoplasmic reticulum in either lymphocytes or FDCs. Our data demonstrate that human lymphoid GCs really contain some of the proteins related to the blood coagulation and fibrinolysis cascades.

Dendritic Cells↗

Alpha 1-adrenergic regulation of thyrotropin-stimulated release of 3, 5, 3' -triiodothyronine and thyroxine from perifused mouse thyroid.

The effect of methoxamine, a specific alpha 1-adrenergic agonist, on the release of T3, T4 and cAMP from perifused mouse thyroid was studied to clarify the role of the alpha 1-adrenergic receptor in the regulation of thyroid hormone secretion. TSH-stimulated T3 and T4 release was inhibited significantly by methoxamine. With regard to cAMP release, methoxamine inhibited TSH-stimulated cAMP release in the presence of 4-(3-butoxy-4-methoxybenzyl)-2-imidazolidinone but did not inhibit TSH-stimulated cAMP release in the presence of 3-isobutyl-1-methylxanthine. Methoxamine did significantly suppress TSH-stimulated release of T3 and T4 in the presence of each phosphodiesterase inhibitor. Depletion of Ca2+ in the perifusion buffer abolished completely the inhibitory effect of methoxamine on TSH-stimulated T3 and T4 release. The present study suggests that activation of the alpha 1-adrenergic receptor inhibits TSH-stimulated T3 and T4 secretion through a Ca(2+)-dependent mechanism in the mouse thyroid gland.

1-Methyl-3-isobutylxanthine↗

Massive sero-epidemiological survey of hepatitis C virus: clustering of carriers on the southwest coast of Tsushima, Japan.

We conducted a mass screening survey for anti-hepatitis C virus antibody (anti-HCV-Ab) among 1,009 inhabitants, 341 males and 668 females, older than 40 years, in south Tsushima in 1989. The overall positive rate for anti-HCV-Ab was 2.3% (2.9% in males and 1.9% in females). The positive rate for anti-HCV-Ab among people with histories of blood transfusions was 14.8% (8/54), which was higher than than (1.6%, 15/955) in people without blood transfusions (P less 0.001). The positive rate (15.1%, 8/53) in people with an elevated level of glutamic oxalacetic transaminase (GOT, greater than or equal to 41 U/liter) or glutamic pyruvic transaminase (GPT, greater than or equal to 36 U/liter) was significantly higher than that (1.6%, 15/956) for people with normal values of GOT and GPT (P less than 0.001). The most interesting finding was that the anti-HCV-Ab positives without histories of blood transfusions were clustered in a few villages located in the southwestern coastal areas of Tsushima, where the positive rate of 3.7% (13/355) was significantly higher (P less than 0.001) than that of 0.3% (2/600) in other villages.

Adult↗

Immunologic and immunohistochemical studies on chronic lymphocytic thyroiditis with or without thyroid lymphoma.

The local immunologic phenomena in the thyroid gland of 16 patients with chronic lymphocytic thyroiditis (CLTH) were investigated; 5 of these cases were associated with thyroid non-Hodgkin's lymphomas (NHL). All patients were admitted because of struma, growing slowly in patients with CLTH alone and rapidly in those with associated thyroid NHL. CLTH was confirmed by histologic findings, including the presence of lymphoid follicles or thyroid autoantibodies in the serum in all 16 patients. Immunologic study revealed that all thyroid NHL were of the B cell type. Surface maker study of suspended cells showed that the percentages of E-rosette-forming cells in patient with CLTH and thyroid NHL (38.0 +/- 10.0%) and in patients with CLTH alone (45.0 +/- 11.9%) were between those of B cell NHL of lymph node and B cell hyperplasia reported by others. Immunohistochemical studies confirmed the reactive nature of lymphoid follicles. Subset distribution of T and B lymphocytes in patients with CLTH and thyroid NHL markedly contrasted with that in patients with CLTH alone: an increased ration of CD8+ cells (suppressor/cytotoxic cell) to CD4+ cells (helper/inducer cell). There was a marked increase in the number of immunosuppressive acidic-protein(IAP)-containing macrophages in the thyroid lesion and serum IAP level in patients with thyroid NHL. These findings provide evidence of a difference in the local immunologic conditions in CLTH alone compared to CLTH complicated by thyroid NHL.

Adult↗

Anti-5-hydroxytryptamine3 effect of galanolactone, diterpenoid isolated from ginger.

It has been reported that an acetone extract of ginger and its fractions have anti-5-HT (5-hydroxytryptamine; serotonin) effects. In the present study, guinea pig ileum, rat stomach fundus and rabbit aortic strips are used in order to determine the constituents of fraction 2 which are responsible for anti-5-HT effect and to examine their pharmacological properties. The analysis of fraction 2-3 indicated that galanolactone, a diterpenoid, is one of the active constituents. In guinea pig ileum, galanolactone inhibited contractile responses to 5-HT with a pIC50 value 4.93. pIC50 value of galanolactone against the response to 2-methyl-5-HT, a selective 5-HT3 agonist, in the presence of methysergide at 1 x 10(-5) M was 5.10. pIC50 values of ICS 205-930, a selective 5-HT3 antagonist, were 5.30 and 7.49, respectively. The concentration-response curve of 5-HT was shown as a biphasic curve and galanolactone caused a selective shift to the right of the second phase. In the same preparations, the pIC50 value of galanolactone and ICS 205-930 against the response to carbamylcholine (CCh) was 4.45 and 4.46. The inhibitory effect of galanolactone on the 5-HT response in the stomach fundus and aortic strips was less than that in the ileum. In addition, in the thoracic aorta precontracted with 50 mM K+, the relaxing effect of galanolactone was about 1/10 of that of papaverine. These results suggest that the anti-5-HT effect of galanolactone, a diterpenoid isolated from ginger, is related to antagonism of 5-HT3 receptors.

Animals↗

Further metabolism of 3,5-di-tert-butyl-4-hydroxybenzoic acid, a major metabolite of butylated hydroxytoluene, in rats.

The metabolic pathway of butylated hydroxytoluene (BHT) to the ring-oxygenated metabolites 2,6-di-tert-butylhydroquinone (BHQ) and 2,6-di-tert-butyl-p-benzoquinone (BBQ) was examined in rats. After intraperitoneal administration of 3,5-di-tert-butyl-4-hydroxybenzoic acid (BHT-acid), which had been regarded as one of the major metabolic end-products of BHT, 2,6-di-tert-butylphenol (DBP) and BBQ were identified in the feces by gas chromatography and gas chromatography-mass spectrometry (GC-MS). The biliary excretion of BBQ, BHQ glucuronide and BHT-acid glucuronide was also confirmed by GC-MS and high-performance liquid chromatography methods. The excretion rate of BHQ glucuronide for 24h after dosing with BHT-acid was about 9-fold higher than that after dosing with BHT. In addition, the formation of BBQ was confirmed in the urine after dosing with DBP. These results suggest that BHT is metabolized to BHQ and BBQ through DBP formed by decarboxylation of BHT-acid.

Animals↗

Inhibitory effects of ionophore A23187 on the release of thyroid hormone and colloid reabsorption in mouse thyroid glands.

The effect of the ionophore A23187 on a. the release of thyroid hormone from perifused mouse thyroid glands and b. the morphological changes in follicular epithelial cells was evaluated. A23187 at a concentration of 5 mumol/l significantly inhibited both the TSH- and the forskolin-stimulated release of T3 and T4. In the presence of 3-isobutyl-1-methylxanthine or (4-(3-butoxy-4-methoxybenzyl)-2-imidazolidinone) RO 20-1724, A23187 did not affect the forskolin-stimulated release of cAMP, but did inhibit the release of T3 and T4 stimulated by forskolin. Light and electron microscopic evaluation of the follicular epithelial cells of mouse thyroid tissues following 1-h stimulation with forskolin showed numerous pseudopods engulfing luminal colloid of various size and the presence of reabsorbed colloid droplets in the apical cytoplasm. Quantitative electron microscopic analysis revealed that the addition of the ionophore A23187 reduced the number of reabsorbed colloid droplets to one eighth in follicular epithelial cells. These observations suggest that the increase in intracellular Ca2+ induced by the ionophore A23187 inhibits the TSH-stimulated thyroid hormone release independently of the cAMP level, and that the suppression of thyroid hormone release may be due to an inhibition of colloid reabsorption.

1-Methyl-3-isobutylxanthine↗

Prognostic factors for pleural lymphoma patients.

Prognostic factors in 47 patients with pleural lymphocytic lymphoma developing in chronic tuberculous pyothorax were evaluated using Cox's proportional hazards model. There were 41 men and six women, aged 44-80 (median 61) years. Approximately 70% of the patients had localized disease in Stages I and II, and 30% advanced disease in Stages III and IV. Histologically, 27 patients had the diffuse large, immunoblastic type and 12 had others. In the other seven patients, histological subtyping of the lymphocytic lymphoma was impossible because of degenerative or necrotic changes in the histologic specimens. A diagnosis of lymphocytic lymphoma of B-cell type was made in one case using combined cytologic and surface maker findings on a cell suspension. In addition, immunologic and immunohistochemical studies revealed another 40 cases to be proven B-cell lymphomas. Poor performance status and elevated levels of BUN and GPT were significantly associated with shortened survival in a Cox's proportional hazards model. A poor performance status and high levels of serum BUN and GPT suggested a marked deterioration in a patient's condition. When compared with previous literature describing prognostic factors in patients with B-cell lymphomas and with lymphocytic lymphomas with unfavorable histologies or associated with long-standing inflammations, the only common prognostic factors was performance status. The significance of primary site in predicting survival from lymphocytic lymphoma is discussed.

Adult↗

Epidemic patterns of hepatitis type B virus (HBV) and human T lymphotropic virus type I (HTLV-I) in two ATL-endemic islands in Kyushu, Japan.

To evaluate the relationships between human T lymphotropic virus type I (HTLV-I) and hepatitis virus type B (HBV) infections, we compared both individual and geographical distributions of carriers of HTLV-I and HBV, and antibody positives to HBV in two ATL-endemic islands in Kyushu, Japan. The positive rates of antibodies to HTLV-I (anti-HTLV-I-Ab) in sera among healthy inhabitants older than 30 years of age were 27.5% (617/2,232) in Nakadohri, Goto Island and 24.0% (500/2,048) in Shimo-agata, Tsushima Island. The positive rates for surface antigen of hepatitis B virus (HBs-Ag) in sera among the same subjects were 6.4% and 2.5%, respectively. In Nakadohri, the age-adjusted positive rates of HBs-Ag and antibody to HBs-Ag (anti-HBs-Ab) in anti-HTLV-I-Ab positives (so-called HTLV-I carriers) differed little from those in negatives. In Shimo-agata, the geographical distribution of HBs-Ag positives (so-called HBV carriers) showed no positive association with that of HTLV-I carriers. These results did not support the positive correlations between HTLV-I and HBV infections among the general population in ATL-endemic areas in Japan.

Adult↗

Regeneration through nerve allografts in the cynomolgus monkey (Macaca fascicularis).

With the use of ulnar nerves of cynomolgus monkeys, the present study examined whether basal laminae of Schwann cells can serve as conduits for regenerating axons in nerve allografts from non-human primates. A segment of ulnar nerve was transected distal to the elbow joint one week before grafting. In Group A, a distal segment of the transected nerve was transplanted, after freezing and thawing, into the ulnar nerve of another monkey, at a level that corresponded to that from which the graft was taken. In Group B (the control group), the segment of nerve was grafted in the same manner but without cryotreatment. Two weeks, five weeks, eight weeks, and five months after grafting, the graft and the host nerve were examined with light and electron microscopy. Within two weeks after grafting in Group A, after degradation of the cellular components of the Schwann cells, the basal laminae of the Schwann cells were intact in the form of tubes. Within five weeks, many regenerating axons grew out into these basal lamina tubes in the three-centimeter-long grafts and extended into the host nerve. As seen at the wrist (seven centimeters from the distal suture) five months after grafting, the axons exhibited fully mature myelination both in the graft and in the host nerve. In contrast, in Group B, in which the Schwann cells had not been disrupted by cryotreatment, cellular components and connective-tissue matrices, including basal laminae, had been degraded and had been replaced by invading cells, which filled the endoneurial spaces of the graft. Five months after grafting, axonal growth had been arrested in the graft one centimeter distal to the proximal suture. The beneficial effect in Group A appears to have been the result of the retention and preservation of intact basal laminae of Schwann cells after rapid removal of killed Schwann cells and myelin debris. Killing of Schwann cells by freezing before grafting may abolish the immune response to the Schwann cells in allografts and lead to fragmentation and disruption of myelin, which facilitates the rapid removal of myelin by macrophages.

Animals↗

[Feasibility study of quality of life (QOL) instrument in patients with advanced lung cancer].

We have studied the feasibility of the QOL measurement for the group of patients with advanced lung cancer using the QOL questionnaires modified from FLIC (Functional Living Index Cancer). The 16-items instrument showed that the Cronbach's alpha of all categories were over 0.6. as the quality of reliability. Using the principal component method of multivariate analysis, four major factors were identified as a part of the construct validity. We concluded that the QOL of patients with advanced lung cancer under the clinical research setting can be evaluated using this questionnaires even in Japan which has different cultural background from the Western Countries.

Adult↗

The 4th nation-wide study of adult T-cell leukemia/lymphoma (ATL) in Japan: estimates of risk of ATL and its geographical and clinical features. The T- and B-cell Malignancy Study Group.

To estimate the annual incidence of adult T-cell leukemia/lymphoma (ATL) by district in Japan, a large-scale nationwide survey of ATL and of non-Hodgkin's lymphoma was performed in 1988. Questionnaires for the registration of ATL and of T-cell and non-T-cell lymphoma were distributed to the physicians in charge of this survey in 1,287 hospitals with 200 or more beds throughout Japan. From the positive rate of anti-HTLV-I antibody in adults, the annual incidence of ATL was estimated at 697, independently of the present survey. In fact, 657 cases (47% of the estimated number), newly diagnosed during the 2 years January 1986 to December 1987, were registered from 191 general hospitals throughout Japan. Major results obtained from the present survey are as follows: (1) among all ATL cases registered, 51% were from Kyushu and 29% were from metropolitan areas (Kanto, Chubu and Kinki) and most, but not all, patients with ATL in the metropolitan areas had come from the ATL-endemic areas and settled in the metropolitan areas; (2) the estimated annual incidence rates of ATL per million adults were 40.4 in males and 26.4 in females in Kyushu, the overall risk of ATL being 1.5 times as high in males as in females; (3) the age-specific incidence rate in Kyushu increased steeply with age until the age of 70, and then decreased markedly in both sexes; (4) the ratio of T-cell versus non-T-cell lymphomas was 2.9 in Kyushu but 0.5 in other districts of Japan, however, this difference regressed to the average for the whole of Japan if ATL cases were excluded; (5) 26.5% of patients with ATL had a family history of cancer, and among these, 14 (8.2%) were ATL, 21 (12.2%) were lymphoma and 17 (9.9%) were hematopoietic malignancies, the incidence of which was markedly higher than in the general population; (6) with regard to clinicopathological features of ATL, there were more advanced cases in south Kyushu than in other districts, however, these differences were not statistically significant. To clarify the chronological changes and geographical variations in the annual incidence of ATL in Japan, continuous systematic nationwide surveillance is necessary and further nation-wide studies are being prepared.

Adult↗

A possible model of hemoprotein-fatty acid peroxide complex demonstrated by electron spin resonance.

Coordination reaction between linolenic-acid-hydroperoxide (LHPO) and chloro(5, 10, 15, 20-tetraphenyl)-porphyrinato iron (III), Fe(III)TPPCl, was investigated by means of ESR. ESR spectra of the ferric low-spin complex (g1 = 2.336, g2 = 2.174 and g3 = 1.929) was recorded for the mixture prepared by mixing Fe(III)TPPCl and LHPO at -78 degrees C in the presence of alkaline reagent. ESR line width of complex was broadened when 17O2 labeled LHPO was used for ESR measurement. In terms of the g-parameters of the ferric low-spin species, this complex was concluded to be Fe(III)TPP(-OCH3)(-OO-linolenic acid) type complex.

Electron Spin Resonance Spectroscopy↗

Diagnostic imaging of diseases affecting the mandible with the use of computed panoramic radiography.

Computed panoramic radiography was performed on patients with bone cyst, osteomyelitis, gingival cancer, and fibrous dysplasia, respectively, to determine the best imaging procedure for disease processes affecting the mandible. Gradational enhancement images for detection of density changes and frequency enhancement images for detecting changes in the margin and texture were effective in aiding the diagnosis of diseases of the mandible with the use of computed panoramic radiography.

Bone Resorption↗